In the field of protective wire nets, it is known to produce protective nets which are constituted by wires that are intertwined with one another. These nets are generally used to construct structures for protecting embankments, rocky slopes, or similar earth structures to prevent the detachment of rocks or the progress of landslides and avalanches which might put roadways, habitations, infrastructures, or heavily frequented areas at risk. Known protective structures are composed of nets of the above-mentioned type which are anchored to the ground by metal stakes or other anchorings which constitute nodal points of the structure.
Frequently, the strength of known nets is not sufficient to withstand the stresses to which they are subjected and it is therefore necessary to superimpose reinforcing cables or panels on the nets by fixing them to the metal stakes or to the other anchorings. In this case, the numerous steps in the fixing of the nets and of the cables or panels, which are generally performed in poorly accessible areas, render the installation of the entire protective structure quite impractical, consequently extending installation times and inevitably increasing installation costs.
The object of the present invention is to solve the problems of the prior art by providing a very reliable and strong protective net, the use of which enables protective structures to be constructed easily, quickly, and at a low cost.
Another object of the present invention is to provide a protective wire net which is of inexpensive construction and which can be produced by a conventional machine operation.
In order to achieve the objects indicated above, the subject of the invention is a protective wire net of the type indicated in the introduction to this description which further comprises one or more longitudinal metal cables, each intertwined with at least one adjacent longitudinal wire.
One of the main advantages of the present invention is the particular tensile strength of the net in the longitudinal direction of the cables included therein. This characteristic enables protective structures to be constructed without additional cables or panels superimposed on the nets, thus reducing installation times and costs. Another advantage of the present invention is that the wires and the cables can be netted simultaneously by means of conventional machines which thus enable the cables to be incorporated in the wire net by means of a single process and to be distributed in accordance with any predetermined pattern.
According to another characteristic of the present invention, transverse wires and/or metal cables may be arranged in a transverse direction relative to the wires and outside or inside intertwining regions defined by portions of adjacent longitudinal wires which are bent around one another. The transverse wires and/or metal cables thus arranged are intertwined or interlaced with one or more of the longitudinal wires.
The main advantage which results from the insertion of transverse wires and/or metal cables is that of increasing the strength of the net in the direction transverse the longitudinal wires in a simple manner. The introduction of the wires and/or cables does not in fact involve modification of the conventional net-production process but purely the addition of a step after the longitudinal wires have been netted.